jsp 自定義分頁標簽

2019-11-18 16:41:31

字體：大中小

來源：轉載

供稿：網友

花了一上午簡單研究了下自定義標簽。就弄了個自定義的分頁標簽。代碼沒有怎么仔細優化。先貼上來，：）

1,標簽的實現類NumenTag.java

import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

import javax.servlet.jsp.JspException;
import javax.servlet.jsp.JspWriter;
import javax.servlet.jsp.tagext.TagSupport;

/** *//**
* 自定義的分頁標簽
*
* @author 馬萬林
*
*/
public class NumenTag extends TagSupport {

PRivate String url = null;

private Result result;

private String page = null;

private String[] p;

private Map kv = new HashMap();

private List key = null;

    /** *//**
     * 分離參數
     * @param params
     */
    public void setParams(String params) {
        key = new ArrayList();
        p = params.split(";");
        for (int i = 0; p.length>1&&i < p.length; i++) {
            kv.put(p[i].split(":")[0], p[i].split(":")[1]);
            key.add(p[i].split(":")[0]);
        }
    }

    /** *//**
     * 分頁的結果
     * @param result
     */
    public void setResult(String result) {
        this.result = (Result) pageContext.getRequest().getAttribute("result");
        this.page = (String) pageContext.getRequest().getAttribute("page");
    }

    public void setUrl(String url) {
        this.url = url;
    }

    public int doStartTag() throws JspException {
        StringBuffer sb = null;
        if (result != null && result.getContent() != null
                && result.getContent().size() > 0) {
            sb = new StringBuffer("分頁: ");
            if (result.getPage().getHasprePage()){
                sb.append("<a href='").append(url);
                if (url.indexOf("?") == -1)
                    sb.append("?page=1");
                else
                    sb.append("&page=1");
                linkParams(sb);
                sb.append("'>").append("首頁").append("</a>").append(" | ");
                sb.append("<a href='").append(url);
                if (url.indexOf("?") == -1)
                    sb.append("?page=").append(
                            result.getPage().getPreviousPage());
                else
                    sb.append("&page=").append(
                            result.getPage().getPreviousPage());
                linkParams(sb);
                sb.append("'>").append("上頁").append("</a>").append(" | ");
            }
            if (result.getPage().getHasNextPage()) {
                sb.append("<a href='").append(url);
                if (url.indexOf("?") == -1)
                    sb.append("?page=").append(result.getPage().getNextPage());
                else
                    sb.append("&page=").append(result.getPage().getNextPage());
                linkParams(sb);
                sb.append("'>").append("下頁").append("</a>").append(" | ");
                sb.append("<a href='").append(url);
                if (url.indexOf("?") == -1)
                    sb.append("?page=").append(result.getPage().getTotalPage());
                else
                    sb.append("&page=").append(result.getPage().getTotalPage());
                linkParams(sb);
                sb.append("'>").append("尾頁").append("</a>");
            }
            sb
                    .append(" 跳轉到:<select name='goToPage' onchange='javascr            int s = result.getPage().getTotalCount();
            for (int i = 1; i <= s; i++) {
                sb.append("<option value=").append(i);
                if (Integer.parseInt(page) == i)
                    sb.append(" selected");
                sb.append(">第").append(i).append("頁</option>");
            }
            sb.append("</select>");
            sb.append("<script language=Javascript>");
            sb.append("function goPage(page){").append("window.location='")
                    .append(url);
            if (url.indexOf("?") == -1)
                sb.append("?page='+").append("page");
            else
                sb.append("&page='+").append("page");
            sb.append("+'");
            linkParams(sb);
            sb.append("';");
            sb.append("}");
            sb.append("</script>");
        }
        try {
            if (sb != null) {
                JspWriter out = pageContext.getOut();
                out.print(sb);
            }
        } catch (Exception e) {
            throw new JspException(e);
        }
        return EVAL_PAGE;
    }

    /** *//**
     * 鏈接參數處理
     * @param sb
     */
    private void linkParams(StringBuffer sb) {
        for (int i = 0; i < key.size(); i++) {
            sb.append("&").append(key.get(i)).append("=").append(
                    kv.get(key.get(i)));
        }
    }